Cell housings associated with batteries commonly include a case and a cap. The case commonly includes a body extending between an inner surface and an outer surface, and the inner surface defines an inner space configured to hold a cell, such as a lithium ion cell, including an electrolyte. The cap generally includes a cap-body extending between a top surface and a bottom surface, and the cap assembly is configured to seal against an open end of the casing to thereby enclose the cell.
One cell housing design is described by U.S. Pat. No. 8,137,833 to Hermann (the '833 patent). As seen there, the '833 patent discloses a case including a body extending between an inner surface and an outer surface, and the inner surface defines an inner space configured to hold a cell, such as a lithium ion cell, including an electrolyte. This case is typically comprised of metal that is non-reactive with the cell, including the electrolyte. Furthermore, the '833 patent discloses a cap assembly including a cap-body extending between a top surface and a bottom surface, and the cap assembly is configured to seal against an open end of the casing to thereby enclose the cell. This cap assembly is also comprised of metal that is non-reactive with the cell, including the electrolyte.
Although the metallic materials used to make the case and the cap of the '833 patent may be non-reactive to the cell and electrolyte, these materials may be susceptible to galvanic or electrolytic corrosion with respect to each other under certain conditions. For example, when condensation or water accumulates at an interface between the case and cap, electrolytic and galvanic corrosion may occur. As a result, the particular battery may fail, which in turn may cause other batteries of a battery pack to fail as well. Therefore, a need exists to provide a cell housing that is not only non-reactive to the cell and electrolyte, but that also minimizes the probability that electrolytic and galvanic corrosion may occur.
The present disclosure is directed to overcoming one or more problems set forth above and/or other problems associated with the prior art.